Temperature sensitive relay or switch



June 6. 9 6 F. w. AUCHMOODY ET AL 2,752,456

TEMPERATURE SENSITIVE RELAY OR SWITCH Filed June 30, 1952 A pf iffy Tiff... '/zI|///////////////////// l ENTORS flan]? WZZza 17191 moody ATTORNEY United States Patent TEMPERATURE SENSITIVE RELAY OR SWITCH Frank W. Auchmoody, Fords, and William F. Brauner,

West New York, N. J., assignors to l e-Ear Laboratories, Summit, N. J., a corporation of New Jersey Application June 30, 1952, Serial No. 296,448

12 Claims. (Cl. 200138) The present invention relates to a temperature sensitive relay or switch which may be utilized in the home, factory, ofiice and in various applications where too high or too low a temperature is to be avoided.

It is among the objects of the present invention to provide a simple, compact, inexpensive lightweight, readily installed temperature sensitive relay or switch which may be broadly utilized to give an alarm or operate a control or signal when the temperature in a certain enclosure, whether it be a room, refrigerator, compartment or other enclosure exceeds a certain predetermined limit or falls below a certain predetermined limit, or both.

Although the present invention has a broad application to temperature control systems in general, it has a particular application to fire alarm systems and particularly fire alarm systems for the home, ofiice, loft, business establishment or the like where it is desirable to have a reliable temperature alarm system which will give adequate and sufficient notice or warning, and which will operate a signal when a predetermined temperature limit has been exceeded.

Still further objects and advantages will appear in the more detailed description set forth below, it being understood, however, that this more detailed description is given by way of illustration and explanation only and not by way of limitation, since various changes therein may be made by those skilled in the art without departing from the scope and spirit of the present invention.

In accomplishing the above objects it has been found most satisfactory, ccording to one embodiment of the present invention, to provide a base or mounted board upon which there may be positioned a lightweight thin arched bimetallic spring leaf element which upon certain temperature changes will move to contact a stop element and establish an electrical circuit.

This electrical circuit may be connected with other relays or it may be associated with a hell or light, or it may actually result in operation of a sprinkler system or a remote warning system, or even operate a heating or cooling apparatus if desired.

In one form of the invention the bimetallic resilient leaf may establish a circuit at each end of its movement and against either stop as for example where one stop will be a normal operating temperature and the other stop will represent an abnormal temperature, causing a certain regulated alarm system or other apparatus to be operated.

Desirably, the bimetallic element and the contents are assembled on a board which in turn may be mounted on a base which may be conveniently fitted into a socket.

Desirably, the entire unit then is enclosed in a cylindrical or tubular housing having a plurality of openings therein so that the air may readily pass into and out of the device and may affect the bimetallic elements.

In the preferred form the entire device is of such a size as to conveniently fit within the palm of the hand and it may be readily placed upon or assembled directly 2,752,456 Patented June 26, 1956 on as a part of a typical switch plate mounted upon the wall of a house, ofiice or factory.

With the foregoing and other objects in view the invention consists of the novel construction, combination and arrangement of parts as hereinafter more specifically described, and illustrated in the accompanying drawings, wherein is shown an embodiment of the invention, but it is to be understood that changes, variations and modifications can be resorted to which fall within the scope of the claims hereunto appended.

In the drawings wherein like reference characters denote corresponding parts throughout the several views:

Fig. 1 is a side prospective view of one of the units of the present invention with the cover assembled thereon and ready for insertion upon a switch plate or other mounting element.

Fig. 2 is a longitudinal side sectional view of the unit of Fig. 1.

Fig. 3 is a longitudinal side sectional view upon the line 3-3 of Fig. 2.

Fig. 4 is a transverse sectional view upon the line 4-4 of Fig. 2 and upon an enlarged scale as compared to Fig. 2.

Fig. 5 is a side sectional view similar to Fig. 3 of an alternative embodiment.

Fig. 6 is a side prospective view showing a plurality of control elements or bimetallic leaf elements of the present invention in side by side relationship as they may be mounted if desired in the units of Figs. 1 to 5.

Referring to Figs. 1 to 4 there is shown a base plate A which carries the upper stop C and the lower stop D.

The base plate A also carries the arched bimetallic element B. The entire base plate, together with its assembed upper and lower contacts C and D and the bimetallic spring B, is mounted on a disk E which carries the wall mounting elements and electrical connection F.

The removable housing G encloses the entire unit while permitting free access of room temperature or area thereto.

The plate A may consist of a laminated or molded plastic sheet or it may consist of a plate of wood or nonconducting material.

As shown best in Fig. 4 the upper contact C consists of a bent piece of metal 10 having the silver contact facing 16 which is held in position at its lower section 12 upon the edge 13 of the portion 13 of the plate A. A rivet such as shown at the right of the plate A in Fig. 4 may be utilized to hold the contact C in position, said rivet extending through the opening 14.

Normally the contact extension 15 of the bimetallic element B will be pressed up against the underface 16 of the contact C when a normal operating temperature is being maintained. The other contact D consists of a metal plate 17 with the silver facings 13 which are held in position by the rivet 19. The contact extension 15 will only contact said lower plate or contact D when an abnormal temperature results requiring the operation of an alarm system, a sprinkler system, or some control apparatus.

The spring element B is soldered or otherwise connected at 20 to the contact extension 15 and it is arched upwardly as indicated at 21, and then downwardly as indicated at 22, and finally inwardly at 23 to rest against the mounting plate A.

The inward extension 23 is held under the plate or strip 24. The leaf element normally is not riveted or otherwise permanently held in position but is bent to approximately the shape shown in Figs. 2 and 3 and then is placed in position with the portion 23 under the strip 24 and extension 15 under the contact C.

The holder strip 24 has an extension plate 25 which is riveted direct as at 26 to the base plate A. Under the rivet 26 is placed the wire 27 which leads down to one of the elements F.

The other rivet 19 may serve as a means of connection for the connector wire 28 which-at its other end is connected by the rivet 23 to the wire 30. The Wires 27 andfitlextend actually through the stepped mounting and connector elements F and they also extend through the D will form asignal unit for mounting into the receiver or enclosure G. This sub-assembly, which may be'readily manufactured with relatively few parts and relatively unskilled labor, can be widely utilized as signal systems or. as atemperature control or switch relay without the enclosure or housing G if desired.

Thelightweight small leaf spring or bimetallic element B, because of its arched shape and relatively loose connectionsunder'the stop. C-and the strip 24, will give'speedy and reliable indication of abnormal temperature by removingitself from the upper stop or contact C and establishing a circuit through the lower stop D, which will operate a signal or alarm system and actuate some other control apparatus. This movement will take place at predetermined temperature range depending upon the initial setting of the bimetallic element B and the curvature indicated at 2ll-2223.

The housing G consists of a cylindrical or tubular metal section at) having a closed end 41 and a serrated grip portion 42. There are a plurality of openings in the right side as indicated at 43 to permit ready flow of air therethrough. The lower portion of the cylinder has the outturned and inturned snap tongues 44 which may be snapped under the periphery of the mounting disk E to hold the cover G in position.

The two mounting connections F lend themselves to be inserted in mounting slots having bayonet connections upon the wall.

In the alternative form as shown in Fig. the base plate A, the disk E, the bimetallic spring B and the upper and lower contacts D and E, as well as the mounting connections F may be of the same construction as in Figs. 1 to 4. However, upon the plate A is mounted the adjustable spring element H provided with an adjustment' J.

The adjustable spring element consists of a leaf spring which may be mounted in position as indicated at 50 and which will have an upwardly bowed resilient portion 51 to press against the arch 2 of the bimetallic element B. The spring member 5t may be pressed adjustably against the arch 21 de ending upon the temperature range it is desired to control. This is accomplished by threading the adjustment rod 52 through the nut 53 which has a serrated knob 54-. This knob will project outwardly through the opening 55 in the side wall of the housing G. By adjustment of the threaded rod 5'2 it is possible to adjust the temperature at which the contact extension will leave the upper contact C and approach the lower contact D.

As shown in Pi gs. l to 5 the contact D is provided with an electrical connection through the posts or mounting elements P. However, if desired, both contacts C and D be active to operate the alarm system or the signal system.

In-the alternative system shown in Fig. 6 there are three bimetallic elements 6%, 61 and 62 having the lead wires 63. as well as the contact plates 64, 65 and 66 with the lead wires 67. A plurality of these elements B, because oftheir small size, may be conveniently mounted in the unit as shown in Fig. 6.

- Thepreferred size of the unit shown in Figs. 1 to 5 may bet" to 2" inlength and /z" to 1" in diameter.

As many changes could be made in the above temperature sensitive relay or switch, and many widely different embodiments of this invention could be made without departing from the scope of the claims, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

Having now particularly described and ascertained the nature of the invention, and in what manner the same is to be performed,

What is claimed is:

l. A temperature sensitive switch or relay comprising a tubular enclosure having perforated side walls, a rectangular mounting insulator plate provided with stop. contact elements and a resilient leaf bimetallic element, a circular transverse insulator base upon which said plate is mounted, and mounting posts and connectors extending through said base, said bimetallic element being of J- shape with the short leg of. the J riveted to the plate adjacent the base and with the end of the long leg terminating at the end of the plate. away from the base and said contact elements extending transversely toward eachv other acrosssaid plate adjacent the end remote from the base and overlapping above and below the end of the long leg of the J, saidpiateextendiug diametrically across substantially the full width and. length of said tubular enclosure and mounted atone edge of said base.

2. A temperature sensitive switch or relay comprising a rectangular mounting insulator plate provided with stop contact elements and a resilient leaf bimetallic element, a circular transve se insulator base upon which said plate is mounted, and mounting posts and connectors extending through said base, and a tubular enclosure detachably mounted upon said base, said bimetallic element being of J-shape with the short leg of the J riveted to the plate adjacent the base and with the end of the long leg terminating at the end of the plate away from the base and said contact elements extending transversely toward each other across said plate adjacent the end remote from the base and overlapping above and below the end of the long leg of the J, said plate extending diametrically across substantially the full width and length of said tubular enclosure and mounted at one edge of said base.

3. A temperature sensitive switch or relay comprising a tubular enclosure having perforated side walls, a rectangular mounting insulator plate provided with stop contact elements and a resilient leaf bimetallic element, a circular transverse insulator base upon which said plate is mounted, and mounting posts and connectors extending through said base, said leaf element consisting of an arched strip which is loosely held upon said plate without being ermanently mounted in position, said bimetallic element being of J-shape with the short leg of the J riveted to the plate adjacent the base and with the end of the long leg terminating at the end of the plate away from the base and said contact elements extending transversely toward each other across said plate adjacent the end remote from the base and overlapping above and below the end of the long leg of the J, said plate extending diametrically across substantially the full width and length of said tubular enclosure and mounted at one edge of said base.

4. A temperature sensitive switch or relay comprising a tubular enclosure having perforated side walls, a rect;.ngular mounting insulator plate provided with stop contact elements and a resilient leaf bimetallic element, a circular transverse insulator base upon which said plate is mounted, and mounting posts and connectors extending through said base, said step contact elements being superimposed and spaced from-one another and said leaf element having an extension positioned between said contact elements, said bimetallic element being of J-shape with the short leg. of the J rivetedto the plate adjacent the base and with the end of the long leg terminating at the end of the plate away from the base and said contact elements extending transversely toward each other across said'plateadjacent the end remote from the base and overlapping above and below the end of the long leg of the J, said plate extending diametrically across substantially the full width and length of said tubular enclosure and mounted at one edge of said base.

5. A temperature sensitive switch or relay comprising a tubular enclosure having perforated side walls, a rectangular mounting insulator plate provided with stop contact elements and a resilient leaf bimetallic element, a circular transverse insulator bate upon which said plate is mounted, and mounting posts and connectors extending through said base and a spring adjustment for said leaf element, said bimetallic element being of J-shape with the short leg of the J riveted to the plate adjacent the base and with the end of the long leg terminating at the end of the plate away from the base and said contact elements extending transversely toward each other across said plate adjacent the end remote from the base and overlapping above and below the end of the long leg of the J, said plate extending diametrically across substantially the full width and length of said tubular enclosure and mounted at one edge of said base.

6. A home fire alarm thermostatic element having a circular flat insulating base, two contact connection posts extending below the base to be mounted upon a wall and to cause said element to extend outwardly transverse to the wall and a diametrically positioned transverse rectangular insulating mounting board extending across and mounted at one end on the opposite side of said base, a J-shaped bimetallic element mounted at the end of its short leg on said board and terminating at the end of its long leg at the upper end of said board and transverse spaced contact strips at the upper end of said board on either side of the end of said leg.

7. The element of claim 6, said strips extending toward each other and spaced above one another from the opposite corners of the upper end of said board and the side of said board opposite said strips being provided with electrical connections to said connection posts, said board being mounted on said base by said posts.

8. The element of claim 6, said element having a detachable cover with a plurality of openings to permit hot air to contact the bimetallic element.

9. A temperature sensitive fire alarm switch device to be mounted upon the switch plate on the wall of a home and to actuate a fire alarm including a circular insulating mounting disk having a pair of outwardly transversely projecting mounting studs with central axial openings and enlarged outside head portions to be mounted on said switch plate, a cylindrical casing having a plurality of spaced round openings in its side wall with a ridged end portion and a blank end outside wall and the inside edges having otfset tongue members to engage the edges of said disk, an insulating mounting board extending diametrically across the interior of said casing substantially the full. width and length thereof, conductor mounting pins extending through said axial openings and said mounting disk and attached to and carrying the end of the board adjacent said disk, at J-shaped bimetallic strip having its short leg mounted on said board adjacent said disk and its long leg extending toward the other end of said board.

10. The device of claim 9, said leg at its upper end having a holder loop at the other end of said board consisting of a U-member extending across and over the end of said long leg of the strip and mounted at its ends upon the upper edge of said board.

11. The device of claim 9, said device having contacts positioned adjacent one edge of said board and wire conductors extending on opposite sides of said board from said mounting pins to said contacts.

12. The device of claim 9, a leaf spring being mounted upon said board intermediate of the ends of said board and inside of said long leg, one end of said leaf spring pressing against said J-strip adjacent its short leg and a bolt adjustment mounted in said board to adjust the amount of pressure exerted upon said leaf spring upon said J-strip.

References Cited in the file of this patent UNITED STATES PATENTS 516,043 Barney Mar. 6, 1894 1,010,414 Cubitt Dec. 5, 1911 1,447,031 Newell, Jr Feb. 27, 1923 1,618,322 Bettenhausen Feb. 22, 1927 1,824,114 Blakeslee Sept. 22, 1931 1,877,131 Hyland Sept. 13, 1932 1,881,919 Patton Oct. 11, 1932 2,035,738 Blanc Mar. 31, 1936 

